Audience measurement of media (e.g., television and/or advertisements) may be carried out by monitoring media exposure to panelists that have been statistically selected to represent one or more particular demographic groups. Audience measurement entities collect audience measurement data. Audience measurement data may include media identification data (e.g., data reflecting the identity of media, such as programming and/or advertisements to which an audience has been exposed) and audience identification data (e.g., data identifying persons who have been exposed to the media, a number of persons in the audience, etc.). Using one or more statistical methods, the collected audience measurement data can be processed to determine, for example, the size and/or demographic composition of the audience(s) for media of interest. The audience size and/or demographic information is valuable to advertisers, broadcasters and/or other entities. For example, audience size and demographic information can be a factor in determining the placement of advertisements, as well as a factor in valuing commercial time slots during particular programs.